Dry sodium chloride forms cubic crystals, while marine aerosol particles often display more or less irregular deviations from this ideal form. In this study, three non‐ideal cuboidal and octahedral model geometries are investigated. Superellipsoids are tested as a model to simulate the linear backscatter depolarization ratio and the extinction‐to‐backscatter ratio. Gaussian random cubes as well as convex polyhedra are investigated as possible model candidates to quantify the error introduced by simplified model geometries, such as superellipsoids. Uncertainties in the real and imaginary part of the refractive index are studied, and their effect on the optical properties is compared to that caused by morphological variations. Optical calculations were performed at a wavelength of 532 nm using the discrete dipole approximation and the T‐matrix method. The considered size range is representative for marine aerosol generated at low to moderate wind speeds. It is found that cuboidal superellipsoids predict depolarization and extinction‐to‐backscatter ratios that are consistent with observations. On the other hand, octahedral superellipsoids strongly overestimate the depolarization ratio. Gaussian random surface perturbations result in a positive shift of the depolarization ratio compared to cuboidal superellipsoids. By contrast, convex polyhedra yield results that more or less randomly scatter about those of regular cubes. Thus, convex polyhedra are a promising candidate for modeling random errors, while Gaussian random cubes are not. Uncertainties in the refractive index result in perturbations of the depolarization and extinction‐to‐backscatter ratio that are of comparable magnitude as those caused by perturbations of the geometry.

中文翻译：

---

非立方海盐粒子的光学特性建模

干燥的氯化钠形成立方晶体，而海洋气溶胶颗粒通常显示出与该理想形式或多或少的不规则偏离。在这项研究中，研究了三种非理想的立方形和八面体模型几何形状。将超椭球体作为模型进行测试，以模拟线性反向散射去极化比和消光与反向散射比。高斯随机立方体和凸多面体被研究为可能的模型候选，以量化由简化模型几何体（例如超椭球体）引入的误差。研究了折射率的实部和虚部的不确定性，并将其对光学性能的影响与形态变化所引起的影响进行了比较。使用离散偶极近似和T矩阵方法在532 nm波长下进行光学计算。所考虑的尺寸范围代表了在低至中等风速下产生的海洋气溶胶。发现立方长椭圆形预测的去极化和消光与背向散射比与观测值一致。另一方面，八面体超椭球体大大高估了去极化率。与立方体的超椭球体相比，高斯随机表面扰动导致去极化比的正向偏移。相比之下，凸多面体的屈服结果或多或少地随机散布在规则立方体的周围。因此，凸多面体是建模随机误差的有希望的候选者，而高斯随机立方体则不是。